Use After Free
CWE-416
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
We track 4,465 vulnerabilities of this type. 100% are rated high or critical, and the average CVSS score is 8.3. 109 have been exploited in real attacks.
How this weakness is prevented
- Architecture and Design: Choose a language that provides automatic memory management.
- Implementation: When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Latest Use After Free vulnerabilities
- 8.0 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind() rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock, but returns the selected listener after dropping that loc
- 8.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: airoha: Fix use-after-free in metadata dst teardown airoha_metadata_dst_free() runs metadata_dst_free() which frees the metadata_dst with kfree() immediately, bypassing the RCU grace peri
- 9.8 Critical severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mtk_eth_soc: Fix use-after-free in metadata dst teardown mtk_free_dev() calls metadata_dst_free() which frees the metadata_dst with kfree() immediately, bypassing the RCU grace
- 8.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: fix use-after-free on first_skb in __input_process_payload __input_process_payload() stores first_skb into xtfs->ra_newskb under drop_lock when starting partial reassembly, then u
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx() Fix the race by pruning the bin while still holding xfrm_policy_lock, before dropping it. Use __xfrm_policy_inexact_p
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: ibm: emac: Fix use-after-free during device removal The driver was using devm_register_netdev() which causes unregister_netdev() to be deferred until the devres cleanup phase, which runs
- 8.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: phy: clean the sfp upstream if phy probing fails Sashiko reported that we don't call sfp_bus_del_upstream() in the probe failure path, so let's add it, otherwise the sfp-bus is left with
- 9.8 Critical severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ipv6: sit: reload inner IPv6 header after GSO offloads ipip6_tunnel_xmit() caches the inner IPv6 header pointer at function entry and continues using it after iptunnel_handle_offloads(). For G
- 9.8 Critical severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: mvpp2: refill RX buffers before XDP or skb use The RX error path returns the current descriptor buffer to the hardware BM pool. That is only valid while the driver still owns the buffer.
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_tunnel: fix use-after-free on object destroy nft_tunnel_obj_destroy() calls metadata_dst_free() which directly kfree()s the metadata_dst, ignoring the dst_entry refcount. Packet
- 8.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free of a deferred file_lock on double SMB2_CANCEL A deferred byte-range lock (an SMB2_LOCK that blocks) registers an async work on conn->async_requests via setup_async_wo
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Forcibly close timer instances at closing When snd_timer object is freed via snd_timer_free() and still pending snd_timer_instance objects are assigned to the timer object, it tri
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: ALSA: timer: Fix UAF at snd_timer_user_params() At releasing a timer object, e.g. when a userspace timer (CONFIG_SND_UTIMER) gets closed and snd_timer_free() is called, it tries to detach the
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: mm/huge_memory: update file PMD counter before folio_put() __split_huge_pmd_locked() updates the file/shmem RSS counter after dropping the PMD mapping's folio reference. If folio_put() drops t
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: zram: fix use-after-free in zram_bvec_write_partial() zram_read_page() picks the sync or async backing device read path based on whether the parent bio is NULL. zram_bvec_write_partial() passe
- 9.8 Critical severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: inet: frags: fix use-after-free caused by the fqdir_pre_exit() flush On netns teardown, fqdir_pre_exit() walks the fqdir rhashtable and flushes every fragment queue that is not yet complete us
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: fix use-after-free of fastrpc_user in workqueue context There is a race between fastrpc_device_release() and the workqueue that processes DSP responses. When the user closes the
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: fix use-after-free race in fastrpc_map_create fastrpc_map_lookup returns a raw pointer after releasing fl->lock. The caller fastrpc_map_create then calls fastrpc_map_get (kref_g
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: net: phonet: free phonet_device after RCU grace period phonet_device_destroy() removes a phonet_device from the per-net device list with list_del_rcu(), but frees it immediately. RCU readers w
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: nvmem: core: fix use-after-free bugs in error paths Fix several instances of error paths in which we call __nvmem_device_put() - which may end up freeing the underlying memory and other resour
- 7.5 High severity
NSD: Use After Free
NSD from version 4.13.0 has a heap use-after-free bug in logging errors on TLS connections, causing a crash of the server process, which can be triggered trivially by sending a DNS query over a DoT connection, and closing the connection without reading the res
- 7.8 High severity
OpenBSD: Use After Free
sys/kern/sysv_sem.c in OpenBSD through 7.9 has a use-after-free allowing local privilege escalation to root. This is a context switch use-after-free after tsleep in sys_semget().
- 7.5 High severity
Gpac: Use After Free
A use-after-free in the gf_filter_pid_inst_swap_delete_task function (/filter_core/filter_pid.c) of GPAC Project/MP4Box before 26.02.0 allows attackers to cause a Denial of Service (DoS) via supplying a crafted media file.
- 8.8 High severity
Chrome: Use After Free
Use after free in Autofill in Google Chrome on Windows prior to 149.0.7827.197 allowed a remote attacker to execute arbitrary code via a crafted HTML page. (Chromium security severity: Critical)
- 7.8 High severity
Chrome: Use After Free
Use after free in WebView in Google Chrome on Android prior to 149.0.7827.197 allowed a local attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)
- 8.8 High severity
Chrome: Use After Free
Use after free in Blink in Google Chrome prior to 149.0.7827.197 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)
- 8.8 High severity
Chrome: Use After Free
Use after free in Bluetooth in Google Chrome on Mac prior to 149.0.7827.197 allowed a remote attacker to execute arbitrary code via a malicious peripheral. (Chromium security severity: High)
- 9.6 Critical severity
Chrome: Use After Free
Use after free in WebGL in Google Chrome on Android prior to 149.0.7827.197 allowed a remote attacker to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: Critical)
- 8.8 High severity
Chrome: Use After Free
Use after free in Blink in Google Chrome prior to 149.0.7827.197 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security severity: High)
- 7.5 High severity
Chrome: Use After Free
Use after free in Web Authentication in Google Chrome prior to 149.0.7827.197 allowed an attacker who convinced a user to install a malicious extension to potentially exploit heap corruption via a crafted Chrome Extension. (Chromium security severity: High)
- 9.6 Critical severity
Chrome: Use After Free
Use after free in WebGL in Google Chrome on Android prior to 149.0.7827.197 allowed a remote attacker to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: Critical)
- 8.8 High severity
Chrome: Use After Free
Use after free in FileSystem in Google Chrome prior to 149.0.7827.197 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)
- 8.8 High severity
Chrome: Use After Free
Use after free in Digital Credentials in Google Chrome on Mac prior to 149.0.7827.197 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. (Chromium security severity: High)
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: fs/mbcache: cancel shrink work before destroying the cache mb_cache_destroy() calls shrinker_free() and then frees all cache entries and the cache itself, but it does not cancel the pending c_
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: PCI: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_o
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: platform/wmi: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: vdpa: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: s390/cio: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the dri
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: s390/ap: use generic driver_override infrastructure When the AP masks are updated via apmask_store() or aqmask_store(), ap_bus_revise_bindings() is called after ap_attr_mutex has been released
- 7.8 High severity
Linux: Use After Free
In the Linux kernel, the following vulnerability has been resolved: bus: fsl-mc: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the